fix: applied filter appenRow focus index (fix #1819)

[IDKNWHORU]

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Description

• Fixed error when filter applied and use focus option in appendRow method
  • it caused by focusAt method parameter issue
  • focus index now refers to filtered data index when filter is non-null.

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Thank you for your contribution to TOAST UI product. 🎉 😘 ✨

[stale[bot]]

This issue has been automatically marked as inactive because there hasn’t been much going on it lately. It is going to be closed after 7 days. Thanks!

[stale[bot]]

This issue will be closed due to inactivity. Thanks for your contribution!